SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e49a7faf28853a012665595b2f07f5797ab9cf16c1e7ea2e75b5a4d205d4202e' 
  AND token = 'vX9QFThrMeX3HQr2hXaRTYMkCo2uIYCD92XBU5SZ2Ek=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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