SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '196469228b4f58702de3cb090c2d4edd32f10076c7115935870075d944082948' 
  AND token = 'xgiXT3C3ZVWYlk/BvxuETJlfJph8cfoyCTEN8wef1sk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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