SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '948c36e5b2250f92933e93d90a4ecb361988c2b486624dcbb3fa1f9418954da2' 
  AND token = 'TYV3tCDX4uIaSTwmH6yCU2tMePQbtA44/LBn2C2FkEE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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