SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3826ae1a8a3ba9c660bc3e7c953482517418297631da46923c0cdba06db08b4a' 
  AND token = 'BPUoiCyCKDvabdijZuhcwTc6xKQ3LYYJbW8aG99yJpo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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