SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '656124d3575fdd81b702d7aae2c0fa9f397245a233800d02aa078daab85defc0' 
  AND token = 'FVMdCPc/rxpCBjPNG8X4a7byPsE/P4FUMUO4BwiFpqk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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