SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5534f100b6957ef4c967e6122167420babf17e92b80079afb3fd3e2626ba4d17' 
  AND token = 'CcWvMmm0XQws8YX2/JbTOr5yKFUCtGRz+TvGhZ24QY8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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