SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd94e0b28f42bef97c9cf60605e6efc45f5b7c11f3f3190ca05a6e9c4abb5249b' 
  AND token = 'Kg8RWeEQYWKgfCP3jQOkm//rRmNDv1TovHOxGKla+YA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}