SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd00ab8d0b23731176a27c0911cb5e65bf7f921262c8ecb46c0fb237deccc11a7' 
  AND token = '2LpVmhRueeX18OtwEJKz2PKO8sFdNZPADuRvEvzEGdY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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