SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'b863877a5931af84cc474c623d63581db021f5418dcd5e9430d11fb2a01431e8' 
  AND token = 'GnbpCYuj1HqSDIJRM+IQZlds7sinpm8T6cdbrWHFSv0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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