SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd8990bd121eea8ef9d637940bae11380dfaefba76d151d528f87d43bbf25c099' 
  AND token = 'w6AzLo0GU5hiWwKCyRYSsawi7a4ip+FzZq0x2ipeudI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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