SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c8dba245b6c9cfd45472dfb81a7c24388fc90b844cb07e08ffa19001695d8f95' 
  AND token = 'Q0MvCcATEgIjw0I2mONI6zFOhEmSNx0ob6xzLiXLYOI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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