SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d05b18cae87dc3de957b90da06b49af30f22c22b3c00b6b5762c8fbf84a79f1' 
  AND token = 'k5WPkli5+TasBv+ZrxWW3n5spTfEMqWx1uC/hR4BRlE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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