SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f82313c1aade2230f42a58bc015cbc83815ebcd1c82693b143c2a1be7e2535fd' 
  AND token = 'QNNh+h2FrBT/h59WW0zQxRBaW6Yj2tcb8JojYG951kk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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