SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d60e7d9aa07768036cda369048fc343f861ac9bea96fe5290b82c2b7011341d' 
  AND token = 'kSSYoyJedugWminDBHV7ZNPxrBWUnHDNiU6bT8Ab1/w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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