SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '73f7a167b9d5c94f5d708d40dee0d746bb82a62d7025a7f9f3d260eda9b60db7' 
  AND token = 'tZhqekuLW1p0o8i5K3Po6XnYtBTBp4u0E23r7X5Ozyw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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