SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5acedaa85d42cb14257c563ba2906793e3f4036b7d57611b7cfaf3d45160fb38' 
  AND token = 'RfJX+oSwblcizy6L6PJiK9U4kBlkcBEbq1pdWVqAcRE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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