SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6aea0980665922e2842e97fca850a0f1b7c1448551eac11ea5407e5504f50994' 
  AND token = 'wyC55TswvVX0+exTWq4Y/W2QtlJuVrIuZ184gBYnr98=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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