SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8c0477a3abd78fe8060914f5310d66f29402fe88960863ac410bb89549775f6e' 
  AND token = 'on5C84D60UmFIogGqXCaXCFpHBNw1HKWB20TXRxvHhY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

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