Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '338c4a20d4313972aa5db196a18e2eb14bae3ba5f9b04099297cc9005f1ff4f5' 
  AND token = '/YLKxpY9Kps7r1qHMS8s5Zn1LGDmJRTITjHy/uAwDfM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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