SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6dde487189d376d27aa01f07d3259f27b5c929ba35fdef459b219403cb0d6d23' 
  AND token = 'BMpL+YUyRoW0puICNz/q8O24gPtJ+NkkJKuy1FVurOI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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