SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'd5a6ef6a302494993882186fff3c7b026bb128bf194dded97509658c495a4fdb' 
  AND token = 'ZQqM6pkN/EPs3IG+c+wdE29VFV4+wXbW2Uz1rzbrJ8s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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