SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b9bd08594d544e5ff9b37b16c65c7b6dc78f00bca9954b1f65f35b932b56f66a' 
  AND token = 'B9+p4vNVY6DtppwRKqu+r84nD5Pk8AgcA8+i+rUN0ig=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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