SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b1c6eeae4ad20e006bba34251d9f47784fffc416ffc9ad264fd98865eb92569' 
  AND token = 'jAe8Bx7iOhCvhYwKEMjPxaUWnNcpAbo1lrmceYcUK7Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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