SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74ec7ca3b795f96462c6453a484a87d63a3f98d24cf19c0a655295c3f26321e0' 
  AND token = 'BRTRvFUzIqnFSHg9pNynH13fHwTgVbAUAos/dOUmkvQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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