Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c8ec3a6e074c8ceb6c37ace5765e574dbf99e8f461ee9c759c9c2e57b0c1400b' 
  AND token = 'qdfBjbdGSsIRI2R2VeetHMbrGj52rRgsFFL/OuUCAoI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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