SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f41953a1590f7720a6d23599efdbcf244d5c3a26e928b99b21450a5d42ef8314' 
  AND token = 'TmgdSOCdMjsayahmMlbgGhfFMaKkuqqdq82PR08nOWI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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