SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37c2323f2b9c26df22894c6837a150c8af868623464788f92fa4dda94d3fdf7c' 
  AND token = 'wuHiR3O0eujSxU8WfdpMDh72MpKdxCmFjmv5qNjhgTA=' 
  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"
    }
  }
}