SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '948dd17ad94f2d8068a5c78bea9deec95c30ec4f20902989d30124767dd5d1d3' 
  AND token = '6gZy11vQ4hm3/nUFWQqJiN2sx/kfOZhzh8/LgD8cVkE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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