SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'c8995efe43efc9590d4e91eb85d34c1260609aedbeba60135da97c118f066095' 
  AND token = 'SHapYFDEJnaJDf8c77wND/KNDjfFuaFZEz08lF3l3pg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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