SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2002914898d59070fab9e412d3ea012ffaf6d2975ddf1e5a072173ebc6d6171' 
  AND token = 'xTbpj1+dFLjjsHF5SzPPzFS8Y2+n5IXSwlLWlmpNMys=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00066

JSON explain

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