SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa582ba0426c28d5e8258d6b082d2ffea4b38c20f1da2cd3fbef41b9ffb0d3b8' 
  AND token = 'BvvFT4EMFLrbu9GYCIsq4MveePR3gfvmFmwEeFa91Zo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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