SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45b2864bc53325bc5e7483d390a332f4a4c41f0e4c2aabc9a8473409dceaccc0' 
  AND token = 'PukEaP+F12P+JsN7wml79NpOmbckjv889ooamEa6Fs8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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