SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4c716920b1300b8a2a66195e4ca66ca7f256468c04638b5d98a09e287cdde26d' 
  AND token = '4hSGfOHkDw3eBZFSClf+gy7XqRVxK2mfVzjurH9y3Zk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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