SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd17464bba29d20c274bf140ec3ca49ecd3f571a6cbee628c8c1f5f1754a5d37' 
  AND token = 'f3N7EXgduW6wZ41UPL3JOArRTalovYkL1XQTwffr8i4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}