SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '44fe8f5e6a7c03d45d5498ec8bd3c8be9a4aec731005b16414fe1788b4512979' 
  AND token = 'bUIVKa/OwBsBKJuKBVEDjjK0+dPO6dqWJbQh/EAMBS0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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