SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '956cf3104ddf8b27d2a16a2c65700eacc75425e86a229ec3ed8769d6d1be651a' 
  AND token = 'Fbdfdug9dSV7BIpTOrxqndPKz16wHpHRhYjRIQ9x8MY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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