SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '280e16991a6affae42c8bfb91d1eae74852a4f84188316da67e00fee04e3e430' 
  AND token = '9xQcNl8GuZLhmXXou3rNZ7oa2KEcP52MEaMXMXlrOnI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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