SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '291d7756eeac5dba55c2f898f89d46797a0c547886cb3fb8d2d6d8af2141a3ea' 
  AND token = 'wfNhmkM4eO6YIU5WdfuxBBq8++coRmFHcs0gA0KwlCk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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