SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '28eac9ccb9a3d5b6bf40cbf88ed61a8caf60f00fc4e28a78c6e342fc38a53ed3' 
  AND token = 'cnAL5S8qHdwOwf/Ef8qrhwfNAx+IQyJQP7q5kmLd0n0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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