SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84c5075169563f825857de195ab33955c2e797503d4af2dec0ec2e144bd67217' 
  AND token = 'cyLOrBEZTOTdoH3MHPzS/KcVVUH1MEX78xzQHou6e5o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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