SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6e2a7524e01cc718425df3b7b11cc7e908e1859cafdc7256b516ce015314f104' 
  AND token = 'zIYFKbXHh3bHpK+fSjhpXncgNz4H9QNYGv6hN38Zhgg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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