SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1b1df2e7b48185e8342e3e7d8382464669db93259790b5866190aabd13a6153b' 
  AND token = 'WVyYZJr8vl9fvUoMkjkrmJjSHjTX+DaqNEtIvdmqDLM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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