Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '842cac1936d341301773b402e8b2d8e384c78f7c47497f50ed1d82d76d0ef232' 
  AND token = 'UqL8hTpsmweHiC/FgfUE00bJAWVeUMXxBaElaPN/WtY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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