SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'abbb62739b45dc4ebcf3db2a8ad5a6669be9f6467226833e80581f1d36d22bf8' 
  AND token = 'RhjXKyAMEN9L10wKlksCof7xFZqpbjuK+ADKIihYFXI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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