SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '12a87139c151c8e37c2d6e603749585caee1e28559fb6356ff90254cbd94593e' 
  AND token = '58SH8Ckxn0qY7cKSUryoFFEWpHvwc7xJh6+rcVlB6Iw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}