SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b2604389c5963326aeaa758243dc0c019a0926ebc595abc23d886426c1ca14ed' 
  AND token = 'qb4N/4ozDJ/O/ujLHJY7hmtvP0q9vFL10pR8CRZiYiw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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