SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30e9baf923588b5f78814657a031e5b23eb8dcafba765558530197d77f238471' 
  AND token = '0MV359vYNhFP0ArBCTGYuSqF3plr/YCsulrqFwZf1yo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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