SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9dadf3a60178c76499124c5c40697c511a421f695919e1242214148c51025c3' 
  AND token = 'jgYhvODHUT1J7mRbkEhnKQymfRL0BRmIUzJ/9TAWuZY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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