SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ceef1ea8978958c4ed89228c006cf449fcb6b38f4deccbcdf3868b120556954' 
  AND token = 'EM1tT/txNHX7wEr6jDrGtSyAvqtBjnuE/GV8QPVXdiM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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