SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7779f0e16242888c7fdcd2fb86295b686594a3f4fe98aeb4fe7d59f32869a687' 
  AND token = 'CBYKHeQh9L+vij/TpJ4dlG2frpuvJlPO18e4KtGMamk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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