SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ab4f54beeed6dd84d62abdd1f8b441311a75fbfa46cc2553ab6075598e78573' 
  AND token = 'uIiAuucU0OosAhzgueGelNE/a8dNV/FGH+k0nO9PNuM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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