SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7cc16b65dcf9129c234c66bdbd1ba5dd983ca8c8b76d04cb0286939e8c85e0d2' 
  AND token = 'CfNwVf8G/Zz/phWRcASGfMhBwPy7mNA95fvOR1Tf/JQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00072

JSON explain

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