SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '026b804ac34ebf5a3769cc6d77313ab9322f1b251dac469d207b88244d171d0b' 
  AND token = 'F0EWicPHmi0uHTz9Ha6w+GIidd0wB99YjjeQ/EMYl1M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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