SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a10907a09790abefdc19a397c56f68af930aa9878d9140bee6f3b4805c96b733' 
  AND token = 'pjNgPYEmee2Xaf8M4e5gHDuqI0n1STPOVFdY097eH2M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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