SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '372b8d6e4448708490e8cb8d905ced1d49d5752787bd1ddf9e8fa92b4e285689' 
  AND token = 'LKwfFfJE3T7oru5K+80qz2cblWrcdsO1HQmtUtrcObo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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