SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7419d9340eec5dac57247e807ba16053002ce5b9888bf0200487bbce884d86a7' 
  AND token = 'ijViDkWPmZeXYuNW/LNNqDYv1o3rA1OKUwraDfrlUL8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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