SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '3819d6a2ff5397eac78be7d3baf1220f3beb27f8b8e40a3dc52517670efbdecf' 
  AND token = 'tEgVG54JfGfJN0KLnE1LM6JThNN2xIoARUzezOjkFlw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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