SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '9cd7f0d4804c0fc5655c6328bde4725890b5e46a4d312f221f16cd42da2660cb' 
  AND token = '+EEZ37i4Fh+77rtwjATKKCKWlHcqgyPimj6rVs9KJlI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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