SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '619b954c5f4120f3103eb8f6eb1d65a151b4ed4091173e1d3559149e80b76431' 
  AND token = 'CXBUZ5hgMcxig1QpGY8D2CLdk79W03XUOc6Qv6dcROY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}