SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '14eee002c835ff33f2bc0ca26a28d72c1ed99783d490e45f815369b3a7e6e35c' 
  AND token = '1p971PP8Bz1RbD/FUvAOvuCGzXNxgIbZIbmpdZNnV7s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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