SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8730003897e85cabe53f07088c4cca70bff85a2f38a9d3d979d3ce2529e72e6d' 
  AND token = 'CMEXdOoHA8OqAoDce/JDNjRg/4qPvQI9aqRKZvECuuY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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