SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '654377ca2d438190d19a25b2258b1bff72139881950ca909ca51b9afeebb0fb3' 
  AND token = 'XDMutbZjgcXOeFmKAN0d2y94v8DwDWvPrEaqM+u9MxM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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