SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ec641784658a8564e461b1a5073c37d030360f19586bf2550f81cc9042ce4f2' 
  AND token = 'X3j5yN/dGXTQmHYRq9vJ0RbXIGk8cgxOTga8bdZDwlk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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