SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4537d8a29f91201b6e60b901e7c787654a908e0e6cc9addb70d30213e57d0431' 
  AND token = 'Pedg/XphNscVOyQoZECoK/zDvvRWuzlHi4+QKyFL94g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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