SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '679b54e140b598867d23431765559c60bc96d7a2c7166bff845c48bcfaf767bd' 
  AND token = 'wSVjd5mGFZoAEx8KCP3nsaGHeb6ho6PRc7iqgs+Y9OM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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