SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30799703ef41ab3745e9d3489131d98265ba2a6ac28da734acf67849607e00c1' 
  AND token = 'wbl6pR2yo8PzGNEG6Yq0qG4Q/xlthYOhFRD57DJ8XBY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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