SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e3de9996e4e7df3ab2748b219f3567d0457a9a273155cc689d8a3551dae18f1f' 
  AND token = 'Ov4ssVt/aTXwJLdQnrqdDGahFBGsenHFreLrrnMF4q0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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