SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2b26c422d8d919bb8087aa3e7c4f55bfa5f9e49ad5cff1b959e531ed0726023' 
  AND token = 'aKY+/o6l96HbuuWswmHpAnvmCR6XMz5Gk+gHJozjFdI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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