SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd4eab710a6a7de56991a41d6e5ea7593d0b63959edb6c608829c1f418db4ddd' 
  AND token = 'HH6THBg2NpvAHRN8GwPhmyuCk/YO+qwS+fHvPo1y9DA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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