SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16b32154af44db086b989172f39ef625f442f5325a672f88c26a27422b3d78d2' 
  AND token = 'an7QNTNd+S/NNWJfJBT2lwE5NA1KUTOOIYbPTz0fxwo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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