SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '0de0a44d5255097f46b7abf467bbe1eacb379b1182e25472f043360dacb74c29' 
  AND token = 'VuCrIzkLxqZfDJzrqUP2yorNMwI4y9dAfMb+vlFZbT4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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