SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ca1d9c215206e3504e879ddad31c09f50e2910664c328ca42138d6113b7594f' 
  AND token = 'vMIwRrdsVl6te9gXvi1+8vIyZK9yz/VVGv0EA5/FedQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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