SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '76eae12a15d6271d5a3869244efbf62f20097599f960c0b1336d1949962f581b' 
  AND token = '5uouWWd3K3Q7FJOwtm8JXJlgMd7tAonTv0wYn/sNqX4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00736

JSON explain

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