SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a81a766cd226d925ea672a2e41a40aaf9a165d81949851b51c719b4df9742c2' 
  AND token = 'VoZLNpS5nTE4Pc14+CuSyYHGqF3RJNoptUGQRF1g1Z4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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