SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '453d8a67adc4741c1ee8980859095ffd26fa64d55a913cd36081f5c3108193a2' 
  AND token = 'YQ6SGcoPnqJmxuVWf//J2DRTTAh5Q1R0OdGTPUf6h0s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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