SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f936f142e9a2002d88519e22879c2b13adb294e5b67d404a06f8a460ce2113f4' 
  AND token = 'VVvm+FZ8Td7L3q9wyMAupx8kdoCJ3pVzH+SeGFchlE4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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