SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '577b07ff4abd73807f9cbef70b1a658746f3715bc898b269a5bdc18b51561910' 
  AND token = '/ZazPNmt7rEdR0gYxy0EEdBMxoQ95krE/O1VfHt+E+E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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