SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '178248c47c63f119e99f8e9a8f3d11f58269d9604658e3c959aaa847db1cda5a' 
  AND token = 'MwTllJuXSK70a6XfPHmCNBkZFogrO6tF9kjJHV2S1QY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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