SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f1ec11291ae48ebc7402ea93fa73b7135f732c305cd193971648de35cc7630bd' 
  AND token = 'vsZLP+ms0ZchKrYL3m64pvmQ7g40dnuYHe2CktrR6aM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}