SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f91be98df24d943599d0697ef17b68265b4078834bccab7fe2c50c5655178872' 
  AND token = 'oajXtO/ZFpwCN4CKmj9oPoLv0xJ4NUiwH0Zs63raR2k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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