Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f35e3617352390f11e4e85abddc502c0b31572180e5abd51fafe763ee32842c' 
  AND token = 'CISp8QEWYcZczN9JAcr97fX8mJDzGewwMdfykKzhtHA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}