SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc181bdc0e9ba95f2570f5af357b6fa4bea1f9d1bd8a41227ffebccf2f42cdf1' 
  AND token = 'VXyXhzohh89pePj33lUEJadgYIj36LfcdSQw6adVfy8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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