SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '98d9964b4ac3a51cf592ffcc2147ccd865545de115e7fd26dcf5b62aa63a103d' 
  AND token = 'cKP0RUk1WeXfLSgkxMm4DKJGckPoWoSPcrbl73CRM6o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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