SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c279544822d50c2025084a2c736304271dede646f20411fbd7613bed084d6efd' 
  AND token = '+Tp4bojaWwtHjiraFdh6VMQi65dlJdnajYEP/wSJiCU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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