SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7f5cfe85da54d0cb912c95f6e69551ebf5898b66ca0aea63da28f84b7d9c4684' 
  AND token = 'OgT5zo4+0C3qTJTBLKOKj8CEcW2fjQAOtwguvIOwubs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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