Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0ad74f0a23ce81be91f59a48ed00d59fae6f33f02af6a9a06ecee862b0bb31a' 
  AND token = '/ImnqEwuLW9HPKYlEWTk8FWp0WTdNqjI2PQbIQf5sg0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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