SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd72305373916f0ab85a7a19ec32e644ae40bdd5b8f752911ef8c6cc023fca27' 
  AND token = 'OLnhDMB6FvgQChDSVJB0JG/bWCrQNjlc+VVLZLJO71g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}