SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b728394b17f06358ae46d940b137fda1bc1e2d8b4b4e2f73dc9d925e64137db' 
  AND token = 'Ffp1PvXUAdpaX9zp1ff1wJ3tv4g6ws7sJJCyojP/TTY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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