SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'daa126f6f974089e3b06f67d0072e6b9233f88d0dfe8a46db76f9d3ff786f542' 
  AND token = '2/0U67abi2Et0ygsI/6zihRTi+k5MDbwckqzD08ydCc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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