Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '62918f51a2b873a509a90f52514cbc07d4fdda87e261df292845babb10b0137d' 
  AND token = 'l4zHG579UFRvxpoeMXbpmfx2eiUnappFhWYMBWOwfYE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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