SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f90ee56e719340b1266a771ce529976333e3bee458c99fab5fba228298624dce' 
  AND token = '2nqICClT/71XBZENycuK4k6DTeUaJsmdUnKzhNjxVe8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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