SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '44bd7985d6755bd9a030a54ec6673254feb558b8135cf6525034154384896bc0' 
  AND token = 'xCXTrww6a4cbQ4Ls+I2srmNhqzdcsPUreZHZW5kwfQI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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