SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8edd8598f60786e8f9dd12c9fdd36e645fcdf7cac7150f5c4d6debdcb6d9ced9' 
  AND token = 'v6CuJGR6J90WTjy7ubwN3TjFDmXjiXDIXLqO7E10NDg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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