SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb9d27eca88cc1044f229132686e54d3b80ab82cb2dfeb3327920e7608c12076' 
  AND token = '8Qt3nrQmrwlKNZaaggdYiHGbteasVjjmCB6mOjSk5gg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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