SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a3bbc9238741940250a87781a6ef7cf8d24eea5c771416583d0fa6f9bcd39874' 
  AND token = 'Mn/WkLuLWofXkQ6OWOLslSRfmV1XCrXQrErBZ0Zr6kI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}