SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3da094118475d396fafd7a2ca14f70ab5d380f4f6aedcb1228117f1e779f2ee5' 
  AND token = '0KqCZC+nPYRo/+wYvmqqDvCkmdrujUsuDlgrLKBRXAM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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