SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b807e13dbf0d11059a51e9a6564b491545940964670ecd8952d4349b0c019a8d' 
  AND token = '+1DDBt9RmK4V9gu3EkFvCCU/eRj2kIPGbV3/prgA9Hw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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