SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92f4e7e03fef694c37cc8fb6cbc383ae39e6136cf7258c9591ca66c72811822f' 
  AND token = 'L2HU1VgZ/uobx426R+k43qefd4zcsqlkWtKhSf3rmXM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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