SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dba5085fa3ef879b8d0776439400a3d638e34bdaf152555599418814561f8645' 
  AND token = 'tQJGmzWbLMIzzQun2viuRzXTSzBY1+kCbnb4g/72Og8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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